Transformer



F. F. BRAND.

TRANSFORMER.

APPLICATION FILED NOV. 21. 1916.

Patented Feb. 24,1920.

F. F. BRAND.

TRANSFORMER.

APPLICATION mu) uov.21.191e.

Patented Feb. 24,1920.

2 SHEETS-SHEET 2- His o lttorney Inventor. F're ericK FIBf-and 8 UNITED STATES PATENT ormon.

FREDERICK F. BRAND, OF PITTSFIELD MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TRANSFORMER.

Specification of Letters Patent.

Patented Feb. 24;, 1920.

Application filed November 21, 1916. Serial No. 132,697.

1 '0 all whom it may concern:

Be it known that I, FREDERICK F. BRAND, a subject of the King of Great Britain, residing at Pittsfield, county of Berkshire, State of Massachusetts, have invented certain new and useful Improvements in Transformers, of which the following is a specification.

My invention relates to transformers, and

particularly to large air blast shell typetransformers. An object of my invention is to improve the ventilation thereof.

The windings and cores of transformers are commonly provided with ventilating spaces for the passage of fluid for cooling or ventilating the same. Air blast transformers are cooled by a blower or pump forcing air through those spaces. As transformers have been commonly constructed before, the ventilatin passages are not straight or unidirectiona but in many cases change their direction throughout their extent, and in many cases a part of each transformer is without effective ventilating passages. Nonunidirectional ventilating passages have been found to collect foreign 'matter deposited by the ventilating fluid, particularly in horizontal sections of such passages. Such foreign matter obstructs the cooling of the apparatus. By my invention, this difiiculty is avoided, and further, the efficient cooling of parts of transformers heretofore inaccessible to the flow of cooling fluid, or made accessible to the fluid flow only with considerable difliculty', is provided for. y

In the accompanying drawings I have illustrated my invention embodied in a large shell type air blast transformer. Figure 1 is a vertical section of the transformer parallel to the planes of the coils. Fig. 2 is another vertical section of the same transformer substantially on the line 22 of Fig. 1. Fig. 3 is a plan view of the top of the core of the transformerof Fig. 1, the coils and various insulation being shown in section. Fig. 4 is a detail of the frame supcoils being vertical. Such a transformer is illustrated in the accompanying drawings. In this particular transformer the entire core comprises two complete adjacent cores 5 and 6 horizontally disposed, located side by side and spaced to provide a ventilating space 7 between the same. Two vertical fillers 8, one at each end of the space 7, close the sides of these spaces. The space 7 aids in cooling the internal legs 10 of the cores and these legs are further provided with ventilating spaces 11, parallel to the ventilating space 7 Ventilating spaces 12 similar to the ventilating spaces 11 are provided in the external legs 13 of the transformer. The winding of the transformer is disposed about the adjacent legs 10. This winding comprises a plurality of thin substantially rectangular coils 18 spaced apart along the winding axis to provide ventilating spaces 19 for the winding. These coils may be insulated from each other and from the core in any one of a number of ways; the insulation per so of the core and winding comprises no part of my invention and may assume various forms so long as it does not obstruct the coolin passages. In order that the embodiment of my invention illustrated may be thoroughly understood, I shall describe the insulation of that transformer in some detail.

In the transformer illustrated the coils are spaced from each other by vertical spacing strips 20 and the cooling fluid and the barrier plates 21 insulate them from each other for the most part.

The winding is insulated from the core by an exterior insulating casing 25 surrounding the same, and a second interior insulating casing 26 substantially surroundingthe internal legs of the core the two casings being joined together by insulating plates 27 opposite the casings. The casings 25 and 26 receive the edges of the coils as illustrated in the figures for aiding the spacing strips 21 in maintaining the coils in their proper relative positions. The interior of the casing 26 is spaced from the internal legs 10 to provide the ventilating passages 28, and likewise the external casing 25 is spaced from the internal legs of the core to provide the ventilating spaces 29. The exterior casing 25 is open at its top and bottom ends as illustrated in Figs. 1, 2 and 5, to provide for the passage of the cooling fluid as indicated by the arrows. The interior casing'26 is provided with slots 30 for the admission and exit of cooling fluid to and from the ventilating spaces 28 as illustrated particularly in Figs. 1 and 5. The interior casing 26 is further provided with two ventilating slots 31 providing for the admission of cooling fluid to the passages 7 and 11 cooling the coils; ventilating slots 32 provide for the exit of the cooling fluid from these ventilating passages in the core. These slots 30, 3l and 32 are at least substantially as long as the ventilating passages they serve are wide, and are '(with the exception of the entrance to the ventilating passage 7) respectively immediately above or below these passages as the case may be. The entrances to and the exits from the ventilating passages 29 are immediately beside the casing 25.

The core and coils are supported by a frame extending along the lower sides of the external legs 13 and the internal legs 10 and also along the lower sides of the yokes joining these legs. The external portion of the frame comprises four .L-pieces 35 forming a rectangle under the external legs 13 and the yokes; between the L-pieces 35 below the yokes, extends an inverted T or double-L member 36, the upright portion of this supporting member extending within the space 7 between the two cores 5 and 6 this space being enlarged about the supporting mem ber 36 to maintain its function as a ventilatingspace. The cross portions of the supporting member 36 are disposed below the internal legs 10 of the core and the under sides of the cross portions rest upon the frame members 35 as shown in Fig. 2. The core is therefore supported about all its lower edges and through its middle between the yokes. Between the supporting members 35 and 36 and the lower faces of the core legs are placed ventilating blocks 37 and 37 respectively, the blocks 37 being most clearly illustrated in Fig. 4; similar ventilating blocks 37 are placed above the 7 core legs 13., and immediately beneath the frame members 38 at the top of the core.

' The ventilating members 37, 3'7, and 37 may be and preferably are provided with a plurality of kerfs 39 which provide for the admission and exit of the ventilating fluid above and below the frame members 35, 36, and 38 and to and from the ventilating passages 7 and 12. Extending downward from the supporting members 35 is a casing 41. This casing totally incloses the lower ends of the coils as illustrated and carries the entire weight of the transformer. In the case of an air blast transformer it further provides for the difection of the air into all the cooling passages. A somewhat similar casing 42 is pro vided above the transformer and connected to the frame members 38. This casing pro-v tects the upper ends of the coils and carries a valve device 43 for controlling the flow of air through the transformer.

In the transformer illustrated the coils are held in vertical position with respect to the core by means of insulating blocks 45 above the internal legs 10 and insulating blocks 46 below these legs. respectively engage the upper and lower inside edges of the coils. Between some of the blocks 46 and the lower-faces of the core are located other blocks 47 and between other blocks 46 and the supporting member 36 immediately above them is the filler block 48. Beneath the insulating blocks 45 are provided the wedges 49 by means of which the coils are tightly seated in their vertical position. These wedges 49 are clearly shown in Fig. 6 and consist of upper and lower parallel strips 50 and 51 respectively having wedge shaped ends 52, which These blocks 7 are sawed off or otherwise removed when r they have been inserted in place to hold the blocks 45 snugly against-the coils 18. It will be observed that the wedges 49 are pro vided with slots in register immediately above the ventilating spaces 7 and 11 and immediately below the slots '32 in the casing 26, and likewise that the insulating blocks v45 are'spaced apart to provide similar co- The slots 32, are of course, in register with the spaces between the blocks'45 and between the wedges 49 to providennidire tional continuations of the ventilating passages 7 and 11.; V 7

It will be observed in this transformer I have provided ventilating passages extending completely through the transformer and that these ventilating passages are each substantially unidirectionah In general I have accomplished this result by providing ventilating passages in and extending lengthwise of the core legs surrounded by the winding and separatingthe coils of the winding to provide ventilating spaces therein at right angles to'and contiiiuations of the core ventilating spaces. It will be quite apparent that no portion of the transformer (except the yokes which are subject to little heating) is without adequate cooling facilities and subject to the direct flow of the cooling fluid. In this connection it may be observed that in transformers of this general type as ,heretoforeconnnonly constructed, the portions of the coils immediately above the legs 10 have been without substantial ventilation or have been. ventilated only with difliculty and by tortuous passages. There is substantially no part of the transformer illustrated and described in which foreign matter may be deposited from the cooling fluid to obstruct the cooling of the device.

While I have described the principle of my invention and the best mode I have contemplated for applying this principle, other modifications will occur to those skilled in this art and I aim in the appended claims to cover all modifications which do not involve a departure from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, 1s:

'1. A transformer comprising a core and a winding thereon, said winding comprising a plurality of coils spaced apart in a direction at an angle to the winding axis to provide a ventilating space, and said core being made of perforated laminations arranged to form a ventilating space interiorly thereof and in conjunction with the first named ventilating space to form a unidirectional ventilating passage through the transformer.

2. A transformer comprising a core and a winding about a leg of that core, said winding comprising a plurality of coils spaced apart in a direction at an angle to the winding axis to provide a ventilating space, and said core leg being provided with an inclosed vertical ventilating space interiorly of the laminations and establishing direct communication between the two parts of the coil space on opposite sides of said core leg.

3. A transformer comprising a core and a winding thereon, said winding comprising a plurality of coils spaced apart to provide a vertical ventilating space, and said core being provided with an inclosed vertical ventilating space interiorly thereof and establishing with the ventilating space of the winding a substantially unidirectional vertical ventilating passage.

4:. A transformer comprising a core and a winding about a horizontal leg thereof, said winding comprising a plurality of coils spaced apart along said leg to provide ventilating spaces, and said leg being provided with a slotted opening forming a. ventilating space therethrough communicating with and at right angles to the COll ventilating spaces. a

5. The combination with a shell type transformer comprising two complete adjacent horizontal cores located side-by-side and spaced to provide a ventilating space therebetween, each of the adjacent legs of said cores being provided with a vertical ventilating space parallel to the space between the cores', and a winding about said adjacent legs of said cores comprising a plurality of coils spaced apart along said legs to provide coil ventilating spaces communicating with the core ventilating spaces, of a vertical filler between said cores at each end of the space therebetween.

6. The combination with a shell type transformer comprising two complete adjacent horizontal cores located side-by-side and spaced to provide a ventilating space therebetween, each of the adjacent legs of said cores being provided with a vertical ventilating space parallel to the space be tween the cores, and a winding about said adjacent legs of said cores comprising a plurality of coils spaced apart along said legs to provide coil ventilating spaces communicating with the core ventilating spaces, of a vertical filler between said cores at each end of the space therebetween, and a frame for supporting the transformer extending along the lower sides of the yokes and the lower sides of the external and internal legs of the cores and provided with passages admitting fluid to the ventilating space between the cores.

7 The combination with a shell type transformer comprising two complete adjacent horizontal cores located side-by-side and spaced to provide a ventilating space therebetween, each of the legs of the cores being provided with a vertical ventilating space parallel to the space between the cores, and a winding about the adjacent legs of said cores comprising a plurality of coils spaced apart along said legs to provide coil ventilating spaces communicating with the core ventilating spaces of said adjacent legs, of a vertical filler between said cores at each end of the space therebetween.

8. The combination with a shell type transformer comprising two complete adjacent horizontal cores located side-by-side and spaced to provide a ventilating space therebetween, each of the legs of the cores being provided with a vertical ventilating space parallel to the space between the cores, and a winding about the adjacent legs of said cores comprising a plurality of coils spaced apart along said legs to provide coil ventilating spaces communicating with the core ventilating spaces of the adjacent legs, of a vertical filler between said cores at each end of the space therebetween, and a. frame for supporting the transformer extending along the lower sides of the yokes and the lower sides of the external and internal legs of the core and provided with passages admitting fluid to the ventilating spaces between the cores and the spaces of the legs thereof.

9.. A transformer comprising a core providi'ng a horizontally disposed core leg, a winding; about said leg, and an insulating casing about said leg Within said Winding, said casing being spaced from one'side of said'leg to provide a ventilating passage 'therebetween and provided with a 'slot through its Walls above and below that ven- 

